That's why we've rounded up 10 prominent fan theories circulating the Internet and given our two cents as to their likelihood. Everyone knew Jon Snow was coming back, right? So they've gotta know some other stuff, too.

A slightly muddled extension of the R + L = J theory that basically argues Meera Reed is Jon Snow's twin sister. Remember that Howland Reed — Meera's supposed father — is the only other man apart from Ned that survives the fight at the Tower of Joy — this theory suggests that Lyanna died while giving birth to twins, and that Ned and Howland took care of one each.

How likely is it?

Okay, so Jon and Meera do look sort of similar, but to be honest we think this one might be a step too far. Having Jon Snow turn out to be the Targaryen heir to the Iron Throne would already be a big enough twist without throwing a secret twin sister into the equation. Add to that the fact that the Meera theory began picking up steam when it looked like Jon might be dead — back when there was a vacancy for a surprise Targaryen heir, in other words — and we reckon this one might have had its day.

A Redditor argues that Sansa dropped plenty of pregnancy hints in Episode 5: She's making a new dress, she can't stomach the food at Castle Black and she says she can "still feel" — physically — Ramsay's assault.

How likely is it?

In the world of the show, this seems like a plausible circumstance. Ramsay wants a Stark heir, right? But it would be a huge deviation from the books — in those, Ramsay marries Jeyne Poole, a friend of Sansa's from Winterfell masquerading as Arya. Ramsay and Sansa never even meet. Plus, there are alternate explanations for all the clues above: Sansa wants a new dress to appear noble when she's recruiting northerners for her army, it doesn't seem like anyone is fond of the food at Castle Black and Sansa certainly doesn't need to be pregnant to feel the effects of Ramsay's abuse.

This one suggests that the ways the Waif (the Paris Geller of Game of Thrones) attacks Arya during training mimic the ways Arya's loved ones have been injured (see GIF above for details). The only injury unaccounted for is a brutal swipe to the ankles — does this mean Rickon's legs are done for? He did just fall into Ramsay's clutches, and Ramsay's not exactly fond of keeping his prisoners fully intact.

How likely is it?

This is a cool analysis, but it might be a bit of overanalysis. Game of Thrones is an incredibly detailed show, but Benioff and Weiss have other stuff to worry about, right? Right? Help.

This one goes hand in hand with the theory that the Umbers are planning to do some Bolton-based back-stabbing. Basically, some people don't think the severed head plonked grimly in front of Ramsay in episode three belonged to Rickon's direwolf Shaggydog. They believe that Shaggy is still alive somewhere, and the head — which could have belonged to a regular, wild wolf — is all part of SmallJon's plan.

How likely is it?

If SmallJon really is double-crossing Ramsay then this one has to be true, right? Well, maybe. It all depends on how cold he is as a character, and how convincing he wants his fake allegiance to look. If SmallJon is double-crossing Ramsay and Rickon knows about it then it seems likely that Shaggy is still alive somewhere; if he's kept Rickon in the dark to make his double-cross more convincing, though, then maybe he really did kill Shaggy to add to the grim authenticity of his plan. The other possibility, of course, is that the Umbers are actually on Ramsay's side; if that's the case, Shaggydog is definitely a goner.

If there's one thing that opens up a hell of a lot of doors for fan theories, it's time travel. This theory has been around for awhile, but it picked up steam again recently after the infamous Bran/Hodor warging incident from episode five. Basically, the theory goes that all the legendary Brans that Old Nan liked to bang on about — Bran the Builder; Bran the Shipwright, etc. — are actually all just one Bran. Our Bran.

How likely is it?

This theory seemed sort of ridiculous at first, but now that we know Bran can indeed influence past events it's starting to seem like more of a possibility. The thing is, we've wasted so much precious screen time watching him plod North to meet the Three Eyed Raven that there needs to be some sort of big payoff at the end. We think Bran is going to become a pretty powerful character, but at this stage we still don't know how powerful. Will he travel back in time and change history, living out entire lives in different ages? Maybe. Or is it more likely that he'll be a mostly silent observer, subtly intervening every now and then to help sculpt events? We think this option could be the more likely of the two.

Man, Rickon's not doing too hot right now. He's lost his direwolf, he's lost Osha and he's trapped in Winterfell with Ramsay. And according to this theory, Rickon's a goner: A Redditor proposes that good ol' Littlefinger (aided by Arryn forces) will attack Winterfell, defeat Ramsay, kill Rickon himself, then plant Sansa as a "puppet wardeness of the North." WTF, Littlefinger.

How likely is it?

If there's one thing we know about Game of Thrones, it's that no one's life is sacred — not even a kid's. Littlefinger's been okay to the Starks in the past, but his ultimate goal is always power — and killing Rickon would put him one step closer to it. Plus, it seems likely from a narrative standpoint that Sansa will end up as the head of House Stark, and that can only happen with Rickon gone. So, yeah, try to disconnect emotionally from Rickon as soon as possible.

We know Bran can alter the past (#HoldTheDoor, y'all), but what if he's responsible for setting the whole show in motion? This theory posits that during a vision into the past, Bran sees King Aerys and tries to reason with him — maybe even warning him about the White Walkers. Unfortunately, all the king hears are whispers, which make him lose his mind and start burning his subjects alive. Thus, sparking the rebellion that caused all this mess. Nice going, Bran.

How likely is it?

We're thinking this one's a keeper. We've already seen Bran influence the past — in fact, we saw him disconcert young Ned Stark when he called out to him at the Tower of Joy. Who's to say he won't disconcert King Aerys, too?

If Maggy the frog's prophecy to Cersei is to be believed, poor King Tommen has to croak at some point. According to this theory, King Tommen will be reunited with Margaery after she's released from the High Sparrow's clutches. In true Margaery fashion, she'll continue to groom Tommen against his mother. Finally, during a moment of high tension (and Game of Thrones is full of them), Tommen will snap at Cersei, and Ser Robert Strong will impulsively tear Tommen to pieces.

How likely is it?

Judging by how quickly the Mountain dispatched that random man who bad-mouthed Cersei after her Walk of Shame, it's clear he's not diplomatic about whom he attacks. In fact, he likely operates under only one instinct — to protect Cersei at all costs. Sure, this theory is contingent on Margaery's freedom and her continued influence over Tommen, but we think it's pretty likely nonetheless. Tommen loves his queen, after all.

Remember how SmallJon Umber delivered Rickon to Ramsay a couple of episodes back? The bearded northerner gave a pretty good speech about how he wanted to team up with the Boltons because he hated wildlings and stuff, but this theory speculates that he's got a hidden agenda and he's really not on Ramsay's side at all.

How likely is it?

It might just be wishful thinking, but we reckon this one's got legs. There's a hell of a lot of evidence to suggest the Umbers would be more likely to go against Ramsay than side with him, and anyway it's about time something went wrong for the show's most sadistic character.

This one's an absolute classic. We don't know who came up with this theory originally, but it's now so popular that many people are pretty much just waiting for it to be confirmed. The basic premise is that Jon Snow isn't Ned's bastard at all, but is actually the son of Rhaegar Targaryen and Lyanna Stark. Fans of this theory believe that Lyanna died in childbirth in the Tower of Joy, and that Ned's final promise to her was to keep her baby (a.k.a Jon Snow/Targaryen) safe.

How likely is it?

It feels more and more likely with each passing episode. Remember that recent Tower of Joy flashback that got cut agonizingly short? Well, the evidence seems pretty clear. Why would Rhaegar station his best fighters outside a remote tower in the middle of a war if they weren't meant to be guarding something important? Why could we hear screams of pain drifting from the window? Why was the Three Eyed Raven worried about Bran seeing inside the tower? A pregnant Lyanna Stark giving birth to a secret Targaryen heir would answer all of these questions.

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